RÉSUMÉ
OBJECTIVE: The role of carbohydrates in weight loss in patients undergoing bariatric surgery (BS) remains poorly understood. Therefore, this study aimed to verify the relationship of the carbohydrate quality index (CQI) with weight loss and cardiometabolic risk markers up to 1 year after BS. MATERIAL AND METHODS: This study included 50 patients with obesity undergoing Roux-en-Y gastric bypass. Data collection was performed preoperatively and 3 and 12 months after surgery. The foods consumed were documented using a 24-h food recall in 3 days. The CQI was calculated considering the following parameters: dietary fiber intake, sugar level; whole grains: proportion of total grains; solid carbohydrate: total carbohydrate ratio. RESULTS: From the total study sample, 58 participants were followed up for 3 months, and eight participants dropped out of the study. The remaining 50 patients were followed up for 12 months. Subjects were classified into tertiles according to the index score. A 1-unit increase in CQI was associated with a -1.02 decrease in insulin concentrations at 12 months and a -1.04 decrease in HOMA-IR. Concerning the total sample, the median of the CQI was 8 points and did not change at 3 and 12 months after surgery, but there was an improvement in some components of the index. CONCLUSION: The data suggest that the quality of carbohydrates can interfere with markers of insulin resistance after BS and the quality of carbohydrates is a point to be guided in patients undergoing BS.